Functions
2.14 Automatic Reclosing System 79
SIPROTEC, 7SJ62/64, Manual
C53000-G1140-C207-2, Release date 01.2008
261
Figure 2-98 Zone sequencing with a fault occurring at Tap Line 5 and at the busbar
2.14.6 Setting Notes
General Settings
The internal automatic reclosure system will only be effective and accessible if address 171 79 Auto Recl.
is set Enabled during configuration. If not required, this function is set to Disabled. The function can be
turned ON or OFF under address 7101 FCT 79.
If no automatic reclosures are performed on the feeder for which the 7SJ62/64 is used (e.g. cables, transform-
ers, motors, etc.), the automatic reclosure function is disabled by configuration. The automatic reclosure func-
tion is then completely disabled, i.e. the automatic reclosure function is not processed in the 7SJ62/64. No mes-
sages exist for this purpose and binary inputs for the automatic reclosure function are ignored. All parameters
of block 71 are inaccessible and of no significance.
Blocking Duration for Manual-CLOSE Detection
Parameter 7103 BLOCK MC Dur. defines the reaction of the automatic reclosure function when a manual
closing signal is detected. The parameter can be set to specify how long the auto reclose function will be
blocked dynamically in case of an external manual close-command being detected via binary input (356
„>Manual Close“). If the setting is 0, the automatic reclosure system will not respond to a manual close-
signal.
Restraint Time and Dynamic Blocking
The blocking time TIME RESTRAINT (address 7105) defines the time that must elapse, after a successful re-
closing attempt, before the automatic reclosing function is reset. If a protective function configured for initiation
of the auto-reclosure function provokes a new trip before this time elapses, the next reclosing cycle is started
in case of multiple reclosures. If no further reclosure is allowed, the last reclosure will be classed as unsuccess-
ful.
In general, a few seconds are sufficient. In areas with frequent thunderstorms or storms, a shorter blocking time
may be necessary to avoid feeder lockout due to sequential lightning strikes or flashovers.
A longer restraint time should be chosen if there is no possibility to monitor the circuit breaker (see below)
during multiple reclosing (e.g. because of missing auxiliary contacts and and information on the circuit breaker
ready status). In this case, the restraint time should be longer than the time required for the circuit breaker
mechanism to be ready.
If a dynamic blocking of the automatic reclosing system was initiated, then reclosing functions remain blocked
until the cause of the blocking has been cleared. The functional description gives further information on this
topic, see marginal heading "Dynamic Blocking". The dynamic blocking is associated with the configurable
blocking time SAFETY 79 ready. Dynamic blocking time is usually started by a blocking condition that has
picked up.
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